1. Field of the Invention
The present invention relates to drug delivery systems, and, in particular, to nebulizing drug delivery devices used in ventilator systems.
2. Description of the Related Art
Conventional ventilator drug nebulizers are known in the medical device industry for use in delivering nebulized particles of a drug solution to a user. Such devices are typically installed in a ventilator circuit such that the gas within the ventilator circuit flows through the nebulizing drug delivery device on its path to the user. Typically, the drug nebulizer has a sealed housing that interfaces with the ventilator circuit, and into which a drug solution is provided. When the drug solution within the drug nebulizer housing is depleted, the housing must be opened in order to be replenished with additional drug solution. In some conventional drug nebulizers, opening the device housing to replenish the drug solution will result in the ventilator circuit being exposed to atmospheric air. Such atmospheric air, if introduced into the ventilator circuit, may be undesirable in certain instances. In other conventional drug nebulizers, while atmospheric air may not enter the ventilator circuit to a significant extent, gas from the ventilator circuit may leak to atmosphere when the nebulizer housing is opened for replenishing drug solution. Again, in some instances such leaking of the ventilator gas flow to atmosphere may be undesirable.